Retaining-valve.



P. E. MARTIN. RETAINING VALVE. APPLICATION FILED JUNB29,1912.

1,076,1 35, Patented 00c. 21, 1913.

uiNrrEn STATES- rfarnnr an on FREDERICK E. MARTIN, or serum, tonIsI'AnA,ASSIGNOR TO SECURITY EQUIPMENT COMPANY, A FIRM coIv rosn or HIMSELF, I.HERMAN McMAI-ION, or DE BIDDER,

' LouIs'IAIvA, AND ROY r. ivionsn, or nnaurlron'r'firnxas.

mirammavn vn.

To all whom it may concern:

'Be it known that I, FREDERICK E. Man- 'rIN,-a citizen of the UnitedStates, residing at Bonami, 1n the parish of Calcasieu and State ofLouisiana, have invented certain new and useful Improvements inRetaining.

Valves; and I do hereby declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same.

My invention relates to improvements in retaining valves, and 1tconslsts 1n the constructlons, cornblnations and arrangements hereindescribed and claimed.

An object of my invention is to provide an improved retaining valve forair-brake systems, in which a reduction of the train-pipe pressure belowa predetermined point will insure the brakes remaining set until thetrainpipe system has been recharged to bring the pressure above suchpredetermined point.

In the accompanying drawings forming a v part of this application, andin which similar reference symbols indicate corresponding parts in theseveral views :Figure 1 is an axial section on the line l1 of Fig. 2,illustrating one embodiment of my invention; and Fig. 2 is a section onthe line 22 of Fig. 1.

Referring to the drawings, 1 indicates a casing which is divided by adiaphragm 2 into a pressure chamber 3 and an exhaust chamber 4providedwith an exhaust outlet 5. The usual triple-valve exhaust pipe 6is connected to a chamber 7 communicating with said chamber 4, and anextension 8 from said pressure chamber 3 is connected to the train-pipeor to the usual auxiliary air reservoir.

A retaining valve 9 controls the communication between the triple-valveexhaust pipe and the exhaust chamber 4; said valve being normally seatedby a spring 10 bearing against a disk 11 which can be adjusted by a bolt12 for varying the tension of said spring to meet all different serviceconditions. 7 V

A spindle 13 is secured to the diaphragm 2 in position for engaging saidretaining valve 9 to unseat the latter, and a valve14 is Specificationof Letters Pate t. I

gagement with said valve.

PatentedOct. 21, 1913. Application filed June 29, 1912. Serial No.706,806. c

In the operation of my invention, the

train-pipe pressure in the pressure chamber 3 normally presses ;thediaphragm 2 out wardly, and causes the spindle 13 carried bysaiddiaphragm to hold the retaining valve 9 from its seat; therebyestablishing communication between the triple-valve exhaust pipe 6 andthe exhaust opening 5 and maintaining the brakes released. It theengineer'no'w' reduces the train-pipe pressure, the springs 10 and 16will force the dia phragm inward against the reduced pressure in thechamber 3, and the retaining valve will be seated to close communicationof the triple-valve pipe 6 with the exhaust opening 5; the reducedpressure in the chamber 3 acting on the diaphragm to maintain the valve14 open and the spindle 13 in engagement' with the seated retainingvalve. In this position of the parts, an increase in the train-pipepressure will act on the relatively large diaphragm 2 to unseat theretaining valve 9 for permitting release of the brakes. Should thetrain-pipe pressure be further reduced below a predetermined point, the

spring 16 will close the valve 14 and withdrawthe spindle 13 fromengagement with the retaining valve; thereby permitting the .air underpressure in the chamber 3 to es cape through the spindle borel8 to theexhaust opening 5. In this position of the parts, the pressure in thetrain-pipe will be effective only on the closed valve 14, which isofless area than the diaphragm 2; therecould be made within the spiritand scope of my invention.

I claim 1. In an air-brake mechanism, a casing, a diaphragm dividingsaid casing into a pres sure chamber and an exhaust chamber providedwith an exhaust opening, means for placing the usual train-pipe andtriple-valve exhaust pipe in communication with such pressure andexhaust chambers, respectively, a retaining valve controlling thecommunication of the'triple-valve exhaust pipe with such exhaustchamber, and a spindle carried by said diaphragm for actuating saidretaining valve, said spindle being provided with a bore opening at theopposlte sides of said diaphragm and controlled by said retaining valve.

2. In an air-brake mechanism, a casing, a diaphragm dividing said easinginto a pressure chamber and an exhaust chamber provided with an exhaustopening, means for placing the usual train-pipe and triple-valve exhaustpipe in communication with such pressure and exhaust chambers,respectively,-a retaining valve controlling the communication of thetriple-valve exhaust pipe with such exhaust chamber, a spindle carriedby said diaphragm for actuating said retaining valve, said spindle beingprovided with a bore opening at the opposite sides of said diaphragm andcontrolled by said retaining valve, and a valve of less area than saiddiaphragm secured to said spindle for controlling communication of thetrain-pipe pressure with such pressure chamber.

In testimony whereof, I aflix my signature, in presence of twoWitnesses.

FREDERICK E. MARTIN. Witnesses:

W. M. MOORE, E. H. JORDAN.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

